Numerical investigation on the effects of non-structural components on the elastic fundamental period of buildings

In this work a parametric study has been performed in order to evaluate the elastic fundamental period of vibration of buildings as function of structural morphology (height, plan area, ratio between plan dimensions) and infills distribution. Recent earthquakes highlighted the significant effects derived from the interaction between structural and non-structural elements on the main dynamic parameters of a structure and the lateral distribution of the inertial forces. Usually, non-structural elements acts together with the structural elements, adding both masses and stiffness. The presence of infill elements is generally not taken into account in the design process of structural elements, although these elements can significantly increase the lateral stiffness of a building leading to a modification in dynamic properties. Particularly, at the Damage Limit State (where an elastic behaviour is expected), soil-structure interaction effects and non-structural elements may further affect the elastic natural period of buildings, changing the spectral accelerations compared with those provided by seismic codes in case of static analyses. Using a numerical campaign, the effects of these parameters on the elastic dynamic behaviour of buildings have been studied taking into account presence and distribution of non-structural elements.